price check on radiant heat stuff

[mlinnane]

WHITE Double Bubble Foil Reflective Foil Insulation 48" (500 sf) II-2B-WHITE-48-B
$114.99 X 4 = $459.00 plus shipping $98 for shipping
The shipping seems very high I am going to start making phone calls around
and see it I can get it locally. Also I am going to check out the tubing as that is all I will need for now. We are going to do the barn in 3 sections
30x40 will section one. Then we will do a 28x45 as section 2 and the thrid section will be 28 X 45. I am going to make a big cut out for the feeds and returns from in the utlity room.
But I feel this quote is high I am not concerned about boiler for now. More then likely going with a closed system, and it will be outdoor wood boiler.
Here is one quote I got the other day from
www.krelldistributing.com
3200 ft of 3/4 barrier pex----- 2624.00 = .82cent a foot seems high
to me. I have seen it from .42 to .54 cents a foot.

1----- Utica SFH 5175 Oil Boiler---- 2800.00
15--- Rolls Vapor barrier/ slab insulation 2070.00 $138 a roll must cover 250 sq feet a roll
1---- Air seperator 95.00
1---- Mixing Valve 180.00
1--- Expansion Tank 67.00
1--- Fill Valve 40.00
2--- Pumps with check valves 280.00

Another thing is the guy never priced any manifolds.

The only thing I need to get done right away is insultation and
the tubing I am going with 3/4 inch. Unless someone has a better reason for a different size tubing?

 

[pekabu]

Did you check out www.RadientTec.com? They are in Lyndonville, VT. Don't know exactly what they have or if they are cheaper but a friend just bought all his materials there.

 

[kmdigital]

My suggestion is don't use the bubble foil. It is mostly a waste of money, except you end up having a very expensive vapor barrier. Sure, the mfg's claim it is the best thing since canned milk, but in reality it has very little insulating value for the money. If you don't believe me, just check the R-value (if you can even find it published anywhere), and you will find that it is very low for direct contact applications. They claim that the aluminum foil works as a radiant barrier, which it does, but ONLY when it is shiny, and it also needs an air space and shouldn't be in direct contact with the heat source to work the best, which you obviously won't have under concrete. Ask yourself, how long will it stay shiny when it is exposed directly to concrete? And what does concrete do to aluminum products?

I used a special radiant blanket in my shop (40x60), that uses two 1/4" layers of closed cell foam, 1 layer of bubble foil, and two layers of aluminum foil all encased inside tough vinyl covers that was designed for this purpose. It is supposed to have an R value of about 7 or 8, plus be a good radiant barrier. It was rather expensive, (around $1,400 if recall correctly) and it works good. But if I had it to do over, I would use plain old high density styrofoam insulation board, either 1-1/2" ( R-7) or 2" (R-10). For the money, you get much better insulation value, less fill is needed if you have to pay for fill sand, and the price per square foot can't be beat. Even Menards now sells the high density board which is designed for this purpose.

As for pipe, I used 1/2" pipe, but you are limited to app 220' Max per individual loop length, while with 5/8" pipe you can go to around 330'. I would have to look up the specs on 3/4", but I assume that you can make each loop app 400' to 450' long. These lengths are based on being able to use the standard inexpensive water lubricated B&G, Taco or Grundfoss circulators which you can buy for about $50, not including a built in check valve. You can obviously increase these lengths by using high head circulators, but they cost at least 2 to 2-1/2 times more, and use more electricity to run.

Smaller pipe is quite a bit cheaper, although you have to use a little more pipe to come back to the manifold more frequently. And the manifold costs are higher as you need more outlets. 3/4" pipe is quite a bit harder to work with as it is stiffer and harder to bend around corners, harder to hold where you want it, etc. But it is much easier to pump the water through long runs of pipe with a smaller, cheaper pump. Generally, most people use smaller pipe due to the cost differences unless they need the larger pipe due to needing to make long runs. Think like across a football field like the Greenbay Packers have at their stadium. Personally, I would use the smaller pipe because it is cheaper and so much easier to work with.

Also, what spacing were you planning for the pipe? I put mine at 24" o.c. in the main area, as the design temp is only 60 degrees, and at 12" o.c. in the future office area for greater comfort (more even floor temps). You have about 3,720 sq ft total, so they must have planned at about 15" o.c. for everything. Assuming that most of it will be used primarily for storage or a shop (not as living space) you can boost this up quite a bit and save on pipe. Sure the floor temp won't be as even, but you won't be able to tell unless you lay on it or walk on it without shoes.

If you are going with an outdoor wood boiler, you will probably want to use a heat exchanger between the radiant system and the boiler. Most outdoor boilers are open systems, which means that you must use only non-ferrous metal (copper, brass or Stainless steel) or plastics for all pipes, valves, pumps, etc on the open system side. Any black pipe or cast iron pumps will quickly rust out in an open system.

I used to design these systems for a living, so I know a few things about them.

 

[kmdigital]

Here is a link to an article about bubble foil. http://www.jlconline.com/cgi-bin/jl...82?c=653664cec206f1da209a1190acc07df1&p=1&q=1

 

[SPIKER]

you might want to try contacting http://www.farmtec.com for a catalog the PEX-AL-PEX was pretty good priced & they have the foil bubble bubble poly materials too, as well as fittings, not sure about pumps ect...

anyhow I bought mine fom them at a good pirce, not sure about the real benifits of the bubble foil stuff or not? ALL of mine was bought a few years back prior to all the major questions about the foil products usefull ness... I was fed a line and took it, as it stands I'll probably end up using it along with 2" of styro boards too... putting the boards down sand & then the bubble stuff.

mark M

 

[graybeard451]

<<WHITE Double Bubble Foil Reflective Foil Insulation 48" (500 sf) II-2B-WHITE-48-B>>
You are better served by 2 rigid foam. There is a link going about this subject on the wall. The wall is another board like this but for heating guys. You can post questions, but if you look around most have already been asked and answered. The link is http://forums.invision.net/Thread.cfm?CFApp=2&Thread_ID=38266&mc=21

Good luck, this is a board that can answer all you questions. Richard